WASHINGTON (AP) -- In a setback for organized labor, Pennsylvania Sen. Arlen Specter said Tuesday he will oppose a bill that would make it easier for workers to form unions.
Specter was the only Republican to support the Employee Free Choice Act two years ago, and unions were hoping he might be the crucial 60th vote needed to overcome an expected GOP filibuster of the measure when it's taken up this summer.
Specter has faced unusually heavy pressure from both labor and business interests and is likely to face a tough Republican primary challenge next year from former Pennsylvania Rep. Pat Toomey. In a statement, Toomey called Specter's decision a "flip flop," prompted by the threat of primary opposition to the five-term senator.
In a floor speech, Specter called the organizing bill a "very emotional issue with labor looking to this legislation to reverse the steep decline in union membership and business expressing great concern about added costs, which would drive many companies out of business or overseas."
Business groups, who have already spent more than $20 million to lobby against the bill, applauded the decision.
"We are commending Sen. Specter for putting American jobs first and opposing card check legislation," said John Engler, president of the National Association of Manufacturers.
Specter said his vote to end a filibuster on the bill two years ago was not support for the merits, but instead for Congress to take up the issue of labor law reform.
Labor leaders quibbled with Specter's recollection of history, noting he was an original co-sponsor of the same bill in 2005. Specter, a moderate, has long been counted among the few GOP lawmakers who have supported unions.
"His statement today opposing an up or down vote and real discussion is inconsistent with his own record of support for working people," said Mary Beth Maxwell, executive director of the pro-union group, American Rights at Work.
AFL-CIO President John Sweeney called Specter's position "frankly, a disappointment and a rebuke to working people, to his own constituents in Pennsylvania and working families around the country."
"We do not plan to let a hardball campaign from Big Business derail the Employee Free Choice Act or the dreams of workers," Sweeney said.
The bill would allow a majority of employees at a company to organize by signing cards, a change from current practice that allows employers to mandate secret ballot elections. It also would boost penalties for retaliation against workers seeking to organize and call for arbitration if management and the union cannot agree on a first contract.
Unions argue that reforms are needed to prevent companies from retaliating against workers who try to organize. Business groups claim secret ballot elections are the only way to prevent union intimidation to sign cards.
Specter agreed with business arguments, calling the secret ballot "the cornerstone of how contests are decided in a Democratic society." And he said the requirement for mandatory arbitration may subject employers to a deal they cannot live with.
His decision will make it difficult for Democratic leaders to move forward with the bill, which unions consider their No. 1 priority but some business groups have labeled "Armageddon."
Senate Majority Leader Harry Reid, D-Nev., played down the announcement.
"Anyone (who) thinks they're burying card check because of Specter's statement in an effort to avoid a primary in Pennsylvania should not think this legislation is going to go away," Reid told reporters.
U.S. Chamber of Commerce president Thomas Donohue warned that there would be other compromise efforts at labor law reform and urged Specter "to oppose these misguided efforts." Indeed, Specter said he might reconsider his position if changes were made to the bill, but indicated that would not happen given the current economic crisis.
Specter sided with business arguments that increasing union membership would lead to increased job losses, making this "a particularly bad time" to enact the bill.
The same bill passed the House in 2007, but failed to overcome a GOP filibuster in the Senate. At the time, 50 Democrats voted for cloture -- or allowing the bill to proceed to a vote -- and 48 Republicans voted against. Specter said the prospects are virtually the same this time around in a chamber with a larger Democratic majority.
If Democrat Al Franken is seated in the contested Minnesota Senate, "it appears that 59 Democrats will vote to proceed, with 40 Republicans in opposition," Specter said. "If so, the decisive vote would be mine."
"In a highly polarized Senate, many decisive votes are left to a small group who are willing to listen, reject ideological dogmatism, disagree with the party line and make an independent judgment," he said. "It is an anguishing position, but we play the cards we're dealt."
Associated Press writer Anne Flaherty contributed to this report.